Model Output Discussion - Into 2024

[Catacol]

@Scott Inghamday.

Vortex split right through the layers to 20hpa (I'll just show the 20)

and vortex clearly very stretched.

ECM signal for fast dropping overall windspeeds at this point midmonth is growing

= little to no top down frictional support for a return of westerlies any time soon.

Meanwhile, as I suggested might be happening a few days ago, relative AAM is on the way back up. Still negative, but climbing and by the time we get to the end of next week I would hazard a guess that the next spike in AAM will be in the wings.

So....playing a game of lag: really cold jumps onto Scott's bandwagon about 15th Jan at a time when the vortex is gasping for air, and at the same point pacific momentum begins to climb again. Remember the Webb prediction of a +EAMT mid month too. This means reamplication roughly from week beginning 29 Jan. Can the cold pattern survive 2 weeks until we get that resurgence?

No way to be sure, other than to look at the products available that are trying to calculate the physics of this. Not surprisingly EC weeklies read week 1 of this pattern as a definite cold to very cold NE for us

by week 2 of the phase a much more muted signal

but hardly one that looks mild. Tentative signs of breakdown? Maybe....but by golly it might be a very snowy breakdown and hardly a breakdown at all given NWP then sees a reignition of those Greenland Heights as we head into February.

I'm going to call it now. I think we have week of cool down with the odd white surprise next week followed by 3 weeks of cool/cold/very cold with snowfall events along the way. I'm not sure there is much of a signal for anything else right now. How much snow falls and where it falls - well, who knows. But snow will be the theme.

And 3 weeks might be pessimistic, because by week 2 of Feb the impacts of the next pacific wave will be in town, and the block will be getting fed plenty. NWP agrees for now.

 

 

Edited January 4 by Catacol

[TSNWK]

1 minute ago, Lukesluckybunch said:

Good gfs run impressive uppers..!

Yep.. about 2 lower across the uk day 4. Nothing in on heights going north at day 5.. now to look out for low pressure from south west around day 8… needs to back off..

[tight isobar]

Gfs 12z is A- typical of a meandering hp-cell that finds a way of cold infer… to add also a classic txt book scenario of cold pool maritime development/ create!!

Edited January 4 by tight isobar

[Jason M]

Well, I think were now pretty nailed on for the initial easterly. Cold but very dry. Pressure is simply too high for any convection and the trend over last 24 hours has been for the heights to increase.

So, its now all about what happens next 

 

[Continental Climate]

35 minutes ago, Ali1977 said:

WOW, I mean this is only 168 - follow that UKMO/GFS 

That is an awesome chart maybe a day away from greatness. Thank god that pesky shortwave has done one. The whole run is better due to that buggering off. 

[tight isobar]

Just now, Jason M said:

Well, I think were now pretty nailed on for the initial easterly. Cold but very dry. Pressure is simply too high for any convection and the trend over last 24 hours has been for the heights to increase.

So, its now all about what happens next 

 

Run with the vents at closer range- it’s ALWAYS optimal- for convection, within close proximity @ 24/ 48 hrs out.. this has legs…trust me

[northwestsnow]

GFS 144 12Z V 6Z

[Ice Day]

UKMO and GFS at 144

 

Both look great at this point

Edited January 4 by Ice Day

[Ali1977]

Just now, northwestsnow said:

GFS 144 12Z V 6Z

High moving earlier again, let’s get this down to day 8 vice 10/12

[Battleground Snow]

Ukmo 144 nice.

Taking the shorter route to deep cold like the icon I think. 168 will be fun

[northwestsnow]

UPGRADE ALERTS all over the gaff

[Ali1977]

Just now, Battleground Snow said:

Ukmo 144 nice.

Taking the shorter route to deep cold like the icon I think. 168 will be fun

I’d love to get this to a point where the professionals start talking about concerns etc…. 

[Mike Poole]

2 minutes ago, Battleground Snow said:

Ukmo 144 nice.

Taking the shorter route to deep cold like the icon I think. 168 will be fun

It won’t get there any faster!

It needs the WAA from the next ridge round west of Greenland, before our high can be sucked up, that is what is driving the timeline.  

Edit - looking at GEM, I’m talking nonsense, that does seem to be going Route 1!

Edited January 4 by Mike Poole

[Lukesluckybunch]

Ukmo brilliant run!heights pushing north..locked in cold from 144 I reckon!can't wait to see the extended there!

Edited January 4 by Lukesluckybunch
Adding

[booferking]

Lol gem moving ahead of the rest.

[Ice Day]

The GEM at 156 

[frosty ground]

1 minute ago, Mike Poole said:

It won’t get there any faster!

It needs the WAA from the next ridge round west of Greenland, before our high can be sucked up, that is what is driving the timeline.  

This run has the high further north and west with low pressure dropping down the east side, the cold is going to get here a few days earlier than the 06z run.

[Battleground Snow]

1 minute ago, Mike Poole said:

It won’t get there any faster!

It needs the WAA from the next ridge round west of Greenland, before our high can be sucked up, that is what is driving the timeline.  

Slightly disagree Mike, as I think our high will get sucked north faster due to the better Arctic high, the 06z gfs was an example of having left over heights too near us.

 

[weirpig]

Much better heights at 168 compared to the gfs  6z run.  Not quite the gem  but upgrades all round at this point 

Edited January 4 by weirpig

[Catacol]

5 minutes ago, Ali1977 said:

I’d love to get this to a point where the professionals start talking about concerns etc…. 

I don't think that will be the language next week. Looking at the strength and location of the block, and given the current mildness and inherent warmth present in water logged ground, we need next week to dry things out and cool things down. We are now guaranteed to get that - frost is going to feature, severe frost for some, and this then sets things up for the week that follows.

I think at that point it is possible the language may change, but it assumes luck in getting snow to fall. Remember that last year we had a cold spell at the start of December, but the trough was slack and lacked the punch to develop much in the way of precipitation. It is too far out to guarantee yet that this time around the flow will be more solid and perhaps carry fronts within it, something we also lacked last year. But it has to be more than just possible that we get luckier with this current, much more potent looking setup.

And then "concern" will follow. As a country we don't deal well with more than about 2cm of snow!

Edited January 4 by Catacol

[Ali1977]

Gem And GFS quite diff at 168, but both looking great

[frosty ground]

 

the position of our high it’s shape will lead to the flood gates being open so much sooner. 
06z below

[northwestsnow]

12z v 6z day 7

 

[ICE COLD]

The GEM 168

[MATTWOLVES 3]

Good God...its been my dad's funeral today..just a small service for close family as he didn't want a big fuss! This may seen insensitive me posting weather charts at such a time..but I will tell you this folks.. My Dad would have been just as excited as many of us and especially at the prospect of snow. Thanks Dad continue to smile down on me..and thanks for so many well wishes over the last couple of weeks.

GEM is well...its a diamond